Chemical Silver plate and aluminum.

[dcorley001]

I'm cleaning up a number of machined aluminum boxes. RF filters, cavity filters etc. These are machind out of aluminum blocks. The covers are just flat stock. These have been plated with silver I'm presuming as an RF shield. My first thought was a 1:1 with distilled water and Nitric. Immersion in the bath just long enough to etch the plate off. Will this allow for recovery of the silver? Is the aluminum going to present issues? Is there a more efficient way? I'm hoping someone else in the forum has a greater education of this type of extraction. Perhaps a working knowledge... Thanks..

 

[Geo]

aluminum is safe to work with nitric acid. aluminum creates an oxidized layer thats impervious to further attack. if the pieces IS aluminum it is safe to strip the silver in nitric acid. scratch deep into the metal to make sure its not copper base metal.

 

[Lou]

They run about 4-5 bucks a pound, these RF waveguides.

 

[lazersteve]

The waveguides also have various other parts mounted in the structure (tuning capacitors, through connectors, adjustment shafts, inductors, etc). Theses parts can be made of other base metals so the dip will need to be monitored as these other metals will not passivate with the nitric mix.

You'll also find some of the guides are plated/painted with coatings that contain other metals that report in the silver solution.

Steve

 

[dcorley001]

Thanks Steve. I'm trying to finish completeley depopulating these before I do anything. My plan was to hand dip these so I could monitor the deplating. I've ordered all of patnors test solutions and won't even start until they arrive. I wasn't sure if a 1:1 or straight nitric bath would be the best approach. I've got a number of projects planned (already ordered your AP dvd and some other supplies for these) Some of these projects have been planned for a bit but I'm doing my best not to allow some fool (me) to get in too big a hurry. Yes, I have the downloaded Hoke. Expect to to see or hear more from me in the forum. the knowledge base here is phenomenol but at times opinionated. I love some of the exchanges but for the most part doesn't reflect the thoughts or logic behind some of the instruction. In short, "you guys are awesome"!!!

 

[nickvc]

It seems you have the makings of a successful refiner. As I'm sure your finding Hoke makes the chemistry understandable and allows you to better understand the debates here on the forum. The one thing in refining that makes you successful is knowledge and getting the basics under your belt allows for different processes and methods to be attempted but as you progress further the variables become more numerous and reaching for reference books becomes second nature as does using the search function here on the forum, bear in mind that no one knows it all, it's just too big a subject.
You are doing the right things and when you feel ready to start I'd suggest writing notes on the process your going to attempt and then checking if it will get you to your objective, leave space to add details and observations as you process your material and once completed that process should be firmly in your mind and any errors can easily be spotted and corrected either by yourself or from those who have done the same process many times. We all make errors and do things wrong but the true refiner knows what he did wrong and how to correct it and that comes from knowledge and experience, two things only you can acquire, so stick at it and I for one am looking forward to seeing your first buttons and bars.